Bobbin support for sewing machines



BOBBIN SUPPORT FOR SEWING MACHINES Filed Dec. 21, 1964 4 Sheets-Sheet l FIT- l INVENTORS BY SMJAMIA: #n

Dec. 26, 1967 YASUKATA EGUH| ETAL 3,359,932

BOBBIN SUPPORT FOR SEWING MACHjINES Filed Dec. 21, 1964 4 Sheets-Sheet 2 INVENTORY I [Mat All Dec. 26, 1967 Filed Dec.

, 4 SheetsSheet 5 INVENTORJ Van/w 1;; E S m-a2 1'1 Dec. 26, 1967 YASUKATA EGUCHI ETAL 3,359,932

BOBBIN SUPPORT FOR SEWING MACHINES Filed Dec. 21, 1964 4 Sheets-Sheet 4 INVENTORS Yam/mu F 4x1;

BY Sign/11a H9 1 United States Patent 3,359,932 BOBBIN SUPPORT FOR SEWING MACHINES Yasukata Eguehi, Tokyo, and Susumu Hanyu, Hachioojishi, Tokyo, Japan, assignors to Janome Sewing Machine Co. Ltd., Tokyo, Japan .Filed Dec. 21, 1964, Ser. No. 419,886 Claims priority, application Japan, Dec. 28, 1963, 38/97,771, 38/97,772 8 Claims. (Cl. 112-218) The present invention relates to sewing machines and, more particularly, the present invention is concerned with a device for supplying sewing thread to the sewing portion of the sewing machine.

It is common practice to supply thread-s from bobbins mounted on the machine. However, in conventional devices generally the possibility of entangling of the slackened thread on its bobbin or around the elongated member on which the bobbin is mounted, is not properly prevented.

Several devices have been heretofore proposed for the purpose of preventing such entangling of the thread, However, all of these devices do not prevent thread entangling with the desired certainty and, furthermore, these devices include rather large and involved mechanisms, or require complicated mounting operations and thus are relatively expensive. Consequently, such devices are generally employed only in connection with industrial sewing machines but not in connection with sewing machines destined for home use.

It is therefore an object of the present invention to provide means for preventing entangling of the thread, which are simple in structure and can be easily installed and which assure with great certainty that no entangling of the thread will take place.

It is a further object of the present invention, to provide a device which in case that the thread unwound from its bobbin becomes slack, will assure that such slackened thread will not become entangled around the bobbin mounting member or any other structural member of the sewing machine.

This is important, particularly when an upper thread is supplied from a bobbin installed on the sewing machine, such thread often becomes slack and hangs down, since the bobbin and the installing bar or mounting member holding the same are mounted for free relative rotational movement. When thread windings around the bobbin, especially windings around the lower portion thereof are paid out and there are no further windings to support the ones currently being paid out below the latter, any slackening in the thread will develop to a large extent. The thus slackened thread will hang downwardly and will either drop into the gap between the end surface of the bobbin and the surface of the bobbin receiving member which forms a supporting seat for the bobbin, or will be caught on the installing or mounting bar or member. If the machine is started to be operated in such condition and the upper thread is paid out, the latter will be entangled on the mounting member and running of the machine will become impossible. The thread will be either cut off, or it will become necessary to untwist the entangled thread which requires time and effort.

It is a further object of the present invention to provide means for' properly paying out the thread during the sewing operation.

In these means or structures of conventional type, due to the fact that the bobbins are either vertically or horizontally disposed, resistance to the rotation of the bobbins during the thread paying out operation is composed of the frictional resistance between the bottom face of the bobbin and the adjacent face of the bobbin receiving 7 3,359,932 Patented Dec. 26, 1967 member, and between the mounting bar or member and the axial bore of the bobbin. Which of these two resistances is the greater one will depend on whether the bobbins are vertically or horizontally disposed.

Particularly, the frictional resistance between the bottom face of the bobbin and the adjacent supporting face of the bobbin receiving member tends to become quite large and, therefore, when the tractive force of the thread surpasses this frictional resistance, rotational movement of the bobbin will be abruptly accelerated and thereby slackening of the thread will be continuously repeated and smooth supply thereof will be impeded. On the other hand, since the contact between a horizontally installing bar and the axial bore of the .body is theoretically contacted only along a line, the frictional resistance therebetween will become too small. Consequently, the horizontally disposed bobbin may be rotated by very slight tractive force and if this force is somewhat increased, a high rotational speed will be obtained. Reduction of this speed causes slackening of the thread and, due to supplying too great a length of thread, proper tightness of the seam produced on the sewing machine will not be achieved.

With the above and other objects in view, the present invention contemplates in a sewing machine, in combination, a bed plate, a sewing machine arm mounted on the bed plate having a front side face facing the operator of the machine and a rear side face, both extending transverse to the bed plate, and bobbin supporting means on the rear side face of the arm and including an elongated mounting member extending substantially parallel to the rear side face and upwardly inclined against the bed plate at an angle less than 30 adapted for rotatably mounting a bobbin thereon.

Thus, according to the present invention, in order to prevent such entangling of the thread, the elongated member on which the bobbin is to be mounted is disposed with an upward inclination and, furthermore, thread guide members are preferably arranged in a position with respect to the corresponding elongated mounting member so that entanglement of the thread will be completely eliminated and smooth operation of the sewing machine with respect to the paying out of thread will be assured.

According to the present invention in order to eliminate improper supply of thread due to too much or too little frictional resistance between the bobbin and its mounting device, the bobbin mounting member is inclined upwardly, preferably within the limits described below, so that in addition to the line contact between the axial bore and the elongated mounting member also a slight degree of friction is obtained between the bottom face of the bobbin and the face of the supporting structure, which faces extend perpendicular to the elongated mounting member and thus also under an oblique angle against the horizontal. Thus, the bobbin may be rotated at the proper speed for supplying thread and, irrespective of the driving speed of the machine, the thread will be smoothly supplied at all times.

Furthermore, according to the present invention a thread supply device is provided wherein falling off of the bobbin from its elongated mounting member cannot take place. In the conventional thread supply devices having horizontally disposed elongated mounting members, as described above, the bobbins may be pulled off the elongated mounting members by the tractive forcerof the thread and possibly may fall off the mounting member. On the other hand, when a conventional sewing machine provided with a vertically disposed mounting member is placed in its case after being turned upside down, then the elongated mounting members will point vertically downwardly and thus will cause falling off of the bob- 3 bins. Therefore, in such case, it is either required to remove the bobbins prior to placing the sewing machine into its case, or to attach suitable cap members to the top of the elongated mounting members for preventing falling off of the bobbins therefrom.

The upward inclination of the mounting members according to the present invention serves toeffectively prevent the bobbin from being drawn off during the sewing operation. Also, since this inclination is relatively slight, preferably less than 30 against the horizontal, there is obtained between the mounting member and the axial bore of the bobbin substantially the same degree of friction as in the case of horizontally disposed mounting bars, and, moreover, since the thread guide member is disposed at an upwardly and laterally spaced position relative to the bobbin, the thread being passed through such guide member will serve to prevent lateral displacement of the bobbin, thereby for all practical purposes preventing the falling off of the bobbin.

Furthermore, the present invention provides a thread supply device which permits smooth mounting of the bobbins on their respective mounting bars and smooth removal of the bobbins therefrom in such cases where a plurality of such mounting bars are disposed on the sewing machine frame, and that a graceful appearance will be maintained and the danger of catching the clothes of the operator with the thread mounting device will be avoided.

Although it is possible to provide several mounting bars Without interference with the mounting and removal of individual bobbins, as long as such mounting bars or members are disposed vertically, these vertical mounting members will extend for a relatively large distance above the upper surface of the arm and this will do harm to the appearance of the machine and might also cause catching and tearing of the clothes of the operator.

On the other hand, while horizontal mounting members do not extend above the body of the machine, a plurality of such horizontal mounting members will make mounting and removal of bobbins onto any one of the mounting members somewhat difficult and impeded by the adjacent mounting member.

In contrast thereto, according to the present invention, due to the inclined position of the mounting members, alignment of their axes is prevented and mounting and removal of the bobbins can be easily accomplished without any interference by adjacent mounting bars or bobbins.

Furthermore, due to the only slight inclination of the mounting bars, the same generally do not extend above the upper face of the arm and thus the good appearance of the machine is maintained and the tendency of the mounting bars to catch the operators clothes is reduced.

It is also possible according to the present invention to place the machine back into its case or the like with great ease. In the conventional machines, the bobbin mounting members are secured to the surface of the machine frame so as to project considerably outwardly therefrom. Therefore, these projecting mounting members may form obstructions when the machine is to be put back into its case and a relatively large case allowing for the space required to accommodate the mounting bars must be provided. However, in accordance with the preferred embodiment of the present invention, the mounting members are retractable relative to the sewing machine arm so that the bars may be retracted to a position close to the arm surface prior to placing the machine into its case, or the mounting bars may be rotated to hang downwardly, whereby the sewing machine can be easily and conveniently put back into its case. Furthermore, by placing the mounting members into such retracted or downwardly hanging position, the arm can be more conveniently gripped and lifted from its case.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

FIG. 1 is a schematic rear view of a sewing machine provided with the thread supplying device according to the present invention;

FIG. 2 is a plan top view of the machine shown in FIG. 1;

FIG. 3 is a rear view of the machine shown in FIG. 1 with two bobbins installed thereon and the thread shown in normal condition;

FIG. 4 is a view similar to FIG. 3 wherein, however, the threads are shown in slackened condition;

FIG. 5 is a rear view of a sewing machine provided with a somewhat modified embodiment of the thread supply device according to the present invention;

FIG. 6 is a top plan view of the sewing machine of FIG. 5;

FIG. 7 is a cross sectional view taken along the line VIIVII in FIG. 6;

FIG. 8 is a cross sectional view of the sewing machine shown in FIG. 9, taken along the line VIIIVIII and showing the bobbin mounting member retracted or pushed into close proximity and partly into the arm; and

FIG. 9 is a rear view of the sewing machine of FIGS. 58, with the bobbin mounting members rotated to different positions.

Referring now to the drawing, and particularly to FIGS. 14 thereof in which a typical embodiment of the present invention is shown, the rear side face 1 of the arm is shown as formed with a plurality of integral projections 2, each projection including a flat bobbin receiving face 7 inclined at an angle of less than about 30, and preferably at an angle between 5 and 20, to a vertical plane perpendicular to the upper surface of bed 9. Elongated mounting members 3 are mounted at the center of each of the bobbin receiving faces 7 extending therefrom at a right angle so that the elongated mounting members extend parallel to each other.

A plurality of bobbins 5 having thread '6 wound therearound are removably mounted on the respective elongated mounting members by receiving in the axial bores of the respective bobbin 5 one of the elongated mounting members 3. Thus, the elongated mounting members 3 and the bobbins mounted thereon will also be inclined with respect to the upper face of bed 9 at an angle of less than approximately 30 and preferably between 5 and 20.

Thread guide means, in form of a plurality of thread guide members 4 are respectively mounted above the bobbin mounting member 3, between the central portion and the forward end portion of the respective elongated mounting member 3. It will be seen that the members 4 each are thus located in areas of the arm which are bounded by two transverse planes substantially normal to the arm and intersecting the ends of the mounting member 3 at an angle relative to the longitudinal axis of the same. Threads 6 are guided by these thread guide members 4 and are passed through suitable means such as, for example, balance 10 and eventually to the respective eye 12 of needle 11 in conventional manner.

The bottom face of bobbin 5 will be in contact with the respective receiving face 7 and the axial bore 8 of bobbin 5 will be in linear contact with the respective mounting member 3, thereby providing proper speed of delivery of threads 6 as described further above to obtain and to cause a uniform paying out of the threads.

Thus, even if-as shown in FIG. 4- the threads have become slack due to paying out a greater length of thread than required during the sewing operation for any reason whatsoever, due to the inclination of the bobbins 5 and the arrangement of the thread guide members 4 above the respective elongated mounting member 3 somewhere between the central and forward end portion thereof, the slackened thread 6' will be vertically suspended downwardly from the respective guide member 4 and will not come too close to the bobbin receiving structure, particularly not to elongated mounting member 3. Consequently, when such slackened threads are subsequently paid out again, for instance upon restarting of the sewing machine, entangling of the threads around the elongated mounting members 3 or other parts of the bobbin receiving device is completely prevented.

Furthermore, the inclination of the elongated mounting members 3 and the positioning of the thread guide member 4 as described above will also serve to prevent disengagement of the bobbin from its supporting elongated mounting member 3 during the sewing operation. Furthermore, since the indicated inclination towards the horizontal of the mounting member and the bobbin causes much greater friction between the same than is available in the case of horizontally disposed elongated mounting members, in the case of a sudden increase of tension in the upper thread, the degree of slackening of threads 6 will be properly limited, and notwithstanding the arrangement, parallel to each other of a plurality of elongated mounting members 3, the individual bobbins can be easily and freely mounted and removed. Thus, according to the present invention a sewing machine is provided which includes a device for supplying thread which is simple in construction, easy to manufacture and assemble and which possesses all of the aforementioned advantages.

The illustrated embodiment may be usedin the case of a single needle operation by mounting only one bobbin on one of the two elongated mounting members, or in the case of a two needle operation, bobbins will be mounted on both elongated mounting members.

In the embodiment illustrated in FIGS. 5-9, the thread supplying bobbin mounting devices include a plurality of somewhat projecting mounting seats 22 extending outwardly from the rear side face of arm 21 of the sewing machine. Mounting seats 22 are formed with bores 34 passing through the center portion thereof into which the end portion of an L-shaped elongated mounting member 23 is inserted. L-shaped elongated mounting members 23 are bent at 33 at a right angle and the portion 25 of the L-shaped mounting member is partially inserted into bore 34. Fastener means such as set screws 36 are provided to fix or clamp portion 25 in bore 34 so that the portion of the elongated mounting member which extends at a right angle to portion 25 and which is to receive the bobbin can be adjusted with respect to its angular inclination, as well as with respect to its distance from the rear side face of arm 21. Bobbin receiving members 27 are mounted on elongated mounting members 23 as illustrated and fixedly secured thereto. By loosening set screw 36, the bent portion 25 of the elongated mounting member will become free to be rotated about the axis of portion 25 and it is thus possible to incline the outer elongated portion of the mounting member at any desired angle. Furthermore, it is possible to push portion 25 more or less deeply into or through bore 34 and thus to control the distance of the outer portion of the elongated mounting member which extends parallel to the rear side face of arm 21 at the desired distance from the latter. In normal operating conditions such as shown in FIGS. 5 and 6, the outer portions 28 of the elongated mounting members will be inclined with respect to the upper surface of the bed at an angle of less than 30, preferably between 5 and 20 and for example about 15 similarly as described further above in conjunction with FIGS. 14.

Under these conditions, in the same manner as shown and described in connection with the embodiment illustrated in FIGS. 14, a plurality of thread guide members 24 are arranged above elongated mounting member portions 28, between the central portions and the forward end portions thereof, and threads (not shown) will be guided by these guide members to eyes 42 of needles 41. Thus, the component parts of the embodiment of the invention illustrated in FIGS. 5-9 are arranged in substantially the same relationship to each other as has been described in connection with FIGS. 1 and 4 and the operational effect and function of the presently described embodiment will be the same as that of the embodiment illus trated in FIGS. 1-4. However, in addition, according to the embodiment illustrated in FIGS. 5-9, the lateral distance of the elongated mounting member from the rear face of the sewing machine arm and the angle of inclination again the horizontal surface of the bed plate 9 and 29 can be adjusted as desired by loosening the respective set screw or fastener means 36.

Thus, for instance, when a sewing machine according to the embodiment illustrated in FIGS. 5-9 is to be placed back into its case or the like, the lateral distance between the portion 28 of the elongated mounting member and the rear side face of the sewing machine arm can be reduced and this will permit also reduction in the width of the sewing machine case.

Moreover, by rotating elongated mounting members 28 so that the same point downwardly, it will be more convenient to raise or hold the upper horizontal portion of arm 21.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of sewing machines differing from the types described above.

While the invention has been illustrated and described as embodied in a thread supplying device of a sewing machine, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. In a sewing machine, in combination, a bed plate; an elongated sewing machine arm mounted on said bed plate having a side face and a top face; bobbin supporting means on said side face of said arm and including an elongated mounting member for one bobbin and extending in a vertical plane substantially parallel to the longitudinal axis of said arm and at angle not exceeding 30 with respect to the horizontal plane, said mounting member having spaced-apart ends and being adapted for rotatably supporting a bobbin; and thread guide means carried by said arm in the region of said top face and being located in an area of said arm bounded by two transverse planes substantially normal to the longitudinal axis of said arm and said planes intersecting said ends of said mounting member at an angle relative to the axis of the latter.

2. In a sewing machine, in combination, a bed plate; an elongated sewing machine arm mounted on said bed plate having a side face and a top face; bobbin supporting means on said side face of said arm and including a pair of elongated mounting members each for one bobbin extending in a vertical plane substantially parallel to the longitudinal axis of said arm at an angle not exceeding 30 with respect to the horizontal plane and being spaced from one another in the direction of said axis, said mounting members each having spaced-apart ends and being adapted for rotatably supporting the respective bobbin; and thread guide means for each of said mounting members and being respectively located in an area of said arm bounded by two transverse planes substantially normal to the longitudinal axis of said arm, said planes intersecting said ends of the respective mounting member at an angle relative to the axis of the latter.

3. In a sewing machine, in combination, a bed plate; an elongated sewing machine arm mounted on said bed plate having a side face and a top face, said side face including an outwardly projecting portion forming a substantially fiat bobbin receiving surface, said receiving surface being upwardly inclined with respect to said top face at an angle of more than 60; an elongated mounting member having spaced-apart ends and being adapted for rotatably supporting a bobbin thereon said mounting member extending upwardly from said receiving surface in a vertical plane substantially parallel to said side face at an angle not exceeding 30 with respect to the horizontal plane and forming a substantially right angle with said flat bobbin receiving surface; and a thread guide member extending upwardly of said top face for receiving thread from said bobbin, said thread guide member being located in a region bounded by two planes extending substantially normal to the elongation of said arm and intersecting said ends of said mounting member at an angle relative to the axis of the latter.

4. In a sewing machine, in combination, a bed plate; an elongated sewing machine arm mounted on said bed plate having a side face and a top face, said side face including an outwardly projecting portion forming a substantially fiat bobbin receiving surface, said receiving surface being upwardly inclined with respect to said top face at an angle of between 70 and 85; an elongated mounting member having spaced-apart ends and being adapted for rotatably supporting a bobbin thereon, said mounting member extending upwardly from said receiving surface in a vertical plane substantially parallel to said side face at an angle not exceeding 30 with respect to the horizontal plane and forming a substantially right angle with said fiat bobbin receiving surface; and a thread guide member extending upwardly of said top face for receiving thread from said bobbin, said thread guide member being located in a region bounded by two planes extending substantially normal to the elongation of said arm and intersecting said ends of said mounting member at an angle relative to the axis of the latter.

5. In a sewing machine, in combination, a bed plate; a sewing machine arm mounted on said bed plate having a front side face facing the operator of the machine and a rear side face, both of said faces extending transverse to said bed plate and said arm being formed with a bore extending inwardly from said rear face; an L- shaped mounting member having a first portion extending into said bore and a second portion perpendicular to said first portion extending parallel to and spaced from said rear side face, said second portion being adapted for rotatably mounting a bobbin thereon; and fastening means for adjustably fixing said first portion of said L-shaped mounting member in said bore and for thereby maintaining a selected distance between said second portion of said mounting member and said rear side face and also maintaining a selected angle between said second portion and said bed plate.

6. In a sewing machine, in combination, a bed plate; a sewing machine arm mounted on said bed plate having a front side face facing the operator of the machine and a rear side face, both of said faces extending transverse to said bed plate and said arm being formed with a bore extending inwardly from said rear face; an L-shaped mounting member having a first portion extending into said bore and a second portion perpendicular to said first portion extending parallel to and spaced from said rear side face, said second portion being adapted for rotatably mounting a bobbin thereon; a flat bobbin supporting member mounted on said first portion adjacent the juncture thereof with said second portion of said mounting member, perpendicular thereto; and fastening means for adjustably fixing said first portion of said L- shaped mounting member in said bore and for thereby maintaining a selected distance between said second portion of said mounting member and said rear side face and also maintaining a selected angle between said second portion and said bed plate.

7. In a sewing machine as defined in claim 5, wherein said arm is formed with an additional bore extending inwardly from said rear face and spaced from the firstmentioned bore in longitudinal direction of said arm; and further comprising an additional L-shaped mounting member having a first portion extending into said additional bore, said fastening means including means for adjustably fixing said first portion of said additional L-shaped member in said additional bore similarly to said first-mentioned L-shaped mounting member.

8. In a sewing machine as defined in claim 7, wherein said mounting members are adjustable independently of one another.

References Cited UNITED STATES PATENTS 132,124 10/1872 Wagner.

578,136 3/1897 Dial et al. 112-163 2,879,734 3/1959 Jones 223 107 X 3,213,815 10/1965 Russmann 112-218 FOREIGN PATENTS 616,006 1/ 1961 Italy.

377,625 6/ 1964 Switzerland.

JORDAN FRANKLIN, Primary Examiner. H. H. HUNTER, Assistant Examiner. 

1. IN A SEWING MACHINE, IN COMBINATION, A BED PLATE; AN ELONGATED SEWING MACHINE ARM MOUNTED ON SAID BED PLATE HAVING A SIDE FACE AND A TOP FACE; BOBBIN SUPPORTING MEANS ON SAID SIDE FACE OF SAID ARM AND INCLUDING AN ELONGATED MOUNTING MEMBER FOR ONE BOBBIN AND EXTENDING IN A VERTICAL PLANE SUBSTANTIALLY PARALLEL TO THE LONGITUDINAL AXIS OF SAID ARM AND AT ANGLE NOT EXCEEDING 30* WITH RESPECT TO THE HORIZONTAL PLANE, SAID MOUNTING MEMBER HAVING SPACED-APART ENDS AND BEING ADAPTED FOR ROTATABLY SUPPORTING A BOBBIN; AND THREAD GUIDE MEANS CARRIED BY SAID ARM IN THE REGION OF SAID TOP FACE AND BEING LOCATED IN AN AREA OF SAID ARM BOUNDED BY TWO TRANSVERSE PLANES SUBSTANTIALLY NORMAL TO THE LONGITUDINAL AXIS OF SAID ARM AND SAID PLANES INTERSECTING SAID ENDS OF SAID MOUNTING MEMBER AT AN ANGLE RELATIVE TO THE AXIS OF THE LATTER. 